Potentilla (gracilis)

Tara Luna USDI NPS - Glacier National Park West Glacier, Montana 59936 (406) 888-7835 http://plant-materials.nrcs.usda.gov/azpmc

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Family Scientific Name:	Rosaceae
Family Common Name:	Rose family
Scientific Name:	Potentilla gracilis Dougl.ex Hook.
Common Name:	Prairie cinquefoil
Species Code:	POTGRA
Ecotype:	Idaho fescue grassland, Big Prairie, Glacier National Park, Flathead Co., MT.,1100m elevation.
General Distribution:	P. gracilis occurs from grasslands to moist areas in deserts to subalpine meadows; Alaska to Baja California, east and south to the Dakotas, Nebraska and New Mexico.ÿ
Propagation Goal:	plants
Propagation Method:	seed
ProductType:	Container (plug)
Stock Type:	160 ml conetainers
Time To Grow:	11 Months
Target Specifications:	Stock Type: Container seedling<br> Height: 6 cm, 4 to 6 true leaves<br> Caliper: n/a<br> Root System: firm plug in conetainer.
Propagule Collection:	Seeds are collected when the achenes turn tan and are easily removed from the receptacle in mid to late August. Seeds are collected in paper bags and kept in a well ventilated drying shed prior to cleaning.
Propagule Processing:	Seeds are cleaned using a hammermill and an office clipper. Seed longevity is at least 5 years at 1 to 3C in sealed containers. Seed dormancy is classified as physiological dormancy. Seeds/Kg: 2,600,000/kg % Purity: 100% % Germination: 40 to 84%
Pre-Planting Treatments:	60 to 120 day cold, moist stratification.
Growing Area Preparation/ Annual Practices for Perennial Crops:	Greenhouse and outdoor nursery growing facility. Sowing Method: Direct Seeding. Seeds are surface sown. Growing medium used is 6:1:1 milled sphagnum peat, perlite, and vermiculite with Osmocote controlled release fertilizer (13N:13P2O5:13K2O; 8 to 9 month release rate at 21C) and Micromax fertilizer (12%S ,0.1%B, 0.5%Cu, 12%Fe, 2.5%Mn, 0.05%Mo, 1%Zn) at the rate of 1 gram of Osmocote and 0.20 gram of Micromax per 172 ml conetainer. Greenhouse temperatures are maintained at 21 to 25C during the day and 16 to 18C at night. Seedlings are hand watered and remain in greenhouse until mid May. Seedlings are then moved to outdoor nursery for the remainder of the growing season. Seedlings are irrigated with Rainbird automatic irrigation system in early morning until containers are thoroughly leached. Average growing season of nursery is from late April after snowmelt until October 15th.
Establishment Phase:	Seeds germinate 7 to 10 days after sowing. Medium is kept slightly moist during germination.
Length of Establishment Phase:	4 weeks
Active Growth Phase:	Root and shoot development occurs rapidly following germination. Seedlings develop 4 to 6 true leaves 4 weeks after germination. Seedlings were fertilized with 20-20-20 liquid NPK at 100 ppm fertilizer during the growing season. Seedlings were fully root tight in 12 weeks and were ready for fall outplanting.
Length of Active Growth Phase:	12 weeks
Hardening Phase:	Seedlings are fertilized with 10-20-20 liquid NPK at 200 ppm during the early fall. Irrigation is gradually reduced in September and October. Plants are leached with clear water before winterization.
Length of Hardening Phase:	4 weeks
Harvesting, Storage and Shipping:	Total Time To Harvest: 10.5 months Harvest Date: September Storage Conditions: Overwinter in outdoor nursery under insulating foam cover and snow.
Length of Storage:	5 months
Other Comments:	P. gracilis is a highly variable species. There are 7 recognized botanical varieties: runnescens, flabelliformis, elmeri, pulcherrima, permollis, gracilis, and glabrata.
References:	Flora of the Pacific Northwest, Hitchcock and Cronquist, 7th edition, University of Washington Press, 1973. Seeding Rate Statistics for Native and Introduced Species, Hassell, Wendel, U.S.D.I. and U.S.D.A., April 1996. Seeds: Ecology, Biogeography, and Evolution of Dormancy and Germination, Baskin and Baskin, Academic Press,1998. Seed Germination Theory and Practice, Deno, Norman, Penn State University, 1993. Glacier National Park Native Plant Nursery Propagation Records, unpublished. Growing Colorado Plants from Seed; A State of the Art, Vol. 3: Forbs, U.S. Fish and Wildlife Service, NTIS General Technical Report, 1982. Seeds: Ecology, Biogeography, and Evolution of Dormancy and Germination, Baskin and Baskin, Academic Press, 1998.

Citation:

Lapp, Joyce; Luna, Tara; Evans, Jeff; Wick, Dale. 2008. Propagation protocol for production of Container (plug) Potentilla gracilis Dougl.ex Hook. plants 160 ml conetainers; USDI NPS - Glacier National Park West Glacier, Montana. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2025/01/02). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.